Bài 1 Tính a) 6/9+1/8 b) 9/9+9/1 c) 7/6 + 9/8 d) 25/45 + 15/12 e) 100/200 + 2000/3000

`a ) 6/9 + 1/8 = 48/72 + 9/72 = (48 + 9)/72 = 57/72 = 19/24`

`b ) 9/9 + 9/1 = 1 + 9 = 10`

`c ) 7/6 + 9/8 = 28/24 + 27/24 = (28 + 27)/24 = 55/24`

`d ) 25/45 + 15/12 = 100/180 + 225/180 = 325/180 = 65/36`

`e ) 100/200 + 2000/3000 = 1/2 + 2/3 = 3/6 + 4/6 = (3 + 4)/6 = 7/6`

`#dtkc`

a) $\frac{6}{9}+$$\frac{1}{8}=$ $\frac{48}{72}+$$\frac{9}{72}=$$\frac{57}{72}=$$\frac{19}{24}$

b) $\frac{9}{9}+$$\frac{9}{1}=$ $\frac{9}{9}+$$\frac{81}{9}=$$\frac{90}{9}=10$

c) $\frac{7}{6}+$$\frac{9}{8}=$ $\frac{56}{48}+$$\frac{54}{48}=$$\frac{110}{48}=$$\frac{55}{24}$

d) $\frac{25}{45}+$$\frac{15}{12}=$ $\frac{300}{540}+$$\frac{675}{540}=$$\frac{975}{540}=$$\frac{65}{36}$

e) $\frac{100}{200}+$$\frac{2000}{3000}=$ $\frac{1}{2}+$$\frac{2}{3}=$$\frac{3}{6}+$$\frac{4}{6}=$$\frac{7}{6}$

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@Rơm